1. Technical Field
The present invention relates to an optical transmission module for transmitting optical signals, a method for manufacturing the optical transmission module, and an electronic device.
2. Background Art
An optical communication network enabling large capacity data communication at high speed is expanding in recent years. Such optical communication network is assumed to be mounted on commercial-off-the-shelf apparatuses in the future. An optical data transmission cable (optical cable) for electric input/output that can be used no different from the current electric cable is being desired for the application of higher speed and larger capacity of data transfer, noise countermeasures, and data transmission between the boards in the device. In the view of flexibility, a film optical waveguide is desirably used for the optical cable.
The optical waveguide is formed by a core having a large index of refraction and a clad being arranged contacting the periphery of the core and having a small index of refraction, where the optical signal entered to the core is propagated while repeating total reflecting at the boundary of the core and the clad. The film optical waveguide has flexibility as the core and the clad are made from soft polymer material.
The optical transmission module mounted with the film optical waveguide having flexibility is disclosed in patent document 1. The optical transmission module disclosed in patent document 1 has a configuration in which an optical chip including an optical element that optically couples with the light transmitted through the optical waveguide and an electrical chip for electrically controlling the optical chip are embedded in a board.
Patent document 2 discloses a flexible print wiring substrate “including a connector attachment portion in which a connector portion is attached on a front surface side, and a reinforcement portion, integrally formed with the connector attachment portion, for reinforcing the connector attachment potion by being folded towards the back surface side of the connector attachment portion”.    Patent Document 1: Japanese Patent Specification No. 3882738 (registered Nov. 24, 2006)    Patent Document 2: Japanese Unexamined Patent Publication No. 2006-156570 (publicized Jun. 15, 2006)